Yum installs wrong version of package with range requirement - centos

Question

I have a semi-complicated setup with multiple repositories that have the same package in it (with a separate team managing the actual repositories).
During our install we are attempting to install a version that satisfies some range by doing: yum install "my-package < 3.0.0"
That was working fine until last week, installing the largest version that was < 3.0.0 (which was 2.5). However, suddenly it started installing version 2.1.0. Is there a way to check why it started that?
When I do yum --showduplicates list my-package it gets the following, so it seems like it should be available:
Installed Packages
my-package.x86_64 2.1.0-1 #codex-released
Available Packages
my-package.x86_64 0.12.0-1 codex-released
my-package.x86_64 1.0.0-1 codex-released
my-package.x86_64 2.1.0-1 codex-released
my-package.x86_64 2.2.0-1 codex-released
my-package.x86_64 2.3.0-1 codex-released
my-package.x86_64 2.4.0-1 codex-testing
my-package.x86_64 2.4.1-1 codex-released
my-package.x86_64 2.4.2-1 codex-testing
my-package.x86_64 2.5.0-1 codex-testing
my-package.x86_64 2.5.1-1 artifactory-testing
my-package.x86_64 3.0.0-1 artifactory-testing
my-package.x86_64 3.0.0-1 codex-testing
Is there any way to find out why it's not installing that higher version?

Answer 1

I guess that it is because of Epoch. Some tools does not display it at all. Compare:
$ rpm -q nmap
nmap-7.60-7.fc27.x86_64
And you can see it only if you ask for more details:
$ rpm -q --qf "%{epoch}:%{version} %{name}\n" nmap
2:7.60 nmap
$ rpm -qi nmap |grep Epoch
Epoch : 2
But the epoch override the version. See:
$ rpmdev-vercmp 3.0.0 1:2.1.0
3.0.0 < 1:2.1.0